29 March 2016

Life is about to get much worse

Climate change is hard for people to understand or take seriously because its FUTURE impacts will be so vast in scale and intensity. It would be easier for people to "believe in" face if its signs were more local and present (one reason I suggested rebranding it "local warming" years ago).

Sadly, it seems that we're about the arrive in that moment of vast intensity a lot quicker than previously forecast.

Last week, James Hansen (one of the first scientists to bring CC to public attention) and many co-authors published an article (link in this summary) explaining how previous estimates of glacial melting in Antartica and Greenland need to be updated to consider positive feedback effects that are hastening the process. These effects are due to the slowing of ocean circulation that will simulataneously mean warmer seas near the Antarctic ice shelves (helping those glaciers slide into the water more quickly) as well as colder seas near Northern Europe (as the "conveyor" of warm water from the Caribbean shuts down).

The upshot of their estimates (which combine data from a past era that had similar GHG concentrations to today's except that today's have accumulated far faster) is that temperatures and storms will be getting much worse in the next 10-20 years (if not now), while sea levels will rise by at least 2m (6 feet) and as much as 6-7m (20 feet) by 2100 -- far higher than current IPCC restimates of 1m.

Unleash the kraken

At least it's not an alien invasion

These results are far more pessimistic than anything the IPCC has put out for three reasons. First, the IPCC operates by consensus, meaning that the most conservative estimates are used. Second, IPCC data and models are in "uncharted territory," so it is not easy to decide if natural systems are going to retard or reinforce man-made trends. Finally, the law of averages means that hundreds of co-authors will tend to agree on a business as usual, linear path of change, rather than the new normal, exponential path that Hansen et al. predict.

What makes me so worried about Hansen et al.'s dire prediction is a separate paper that I was reading in advance of my upcoming class. Martin Weitzman has been heavily involved in CC economics for several decades, and his 2011 paper "Fat-Tailed Uncertainty in the Economics of Catastrophic Climate Change" [pdf] explains how we (economists) have underestimated risk on 4-5 dimensions, meaning that our models are inaccurate. As an example, Weitzman explains how an average 10 degree increase in temperatures -- a change that would mean "the earth was ice free, while palm trees and alligators lived near the North Pole" -- shows up in models as a 0.1 percent drop in long run GDP growth (from 2.0 to 1.9%). Weitzman points out that such models are incompatible with results where "half of today’s human population would be living in places where, at least once a year, there would be periods when death from heat stress would ensue after about six hours of exposure... i.e., temperatures that would represent an extreme threat to human civilization and global ecology as we now know it."

The upshot is that economic cost-benefit models may be radically understating the cost of climate change (in exactly the same way as they failed to predict the financial crisis), which means that most discussions are far too conservative about the need to act quickly to reduce GHG emissions.

What will the Dutch do?
These two papers put a fine point on the dangers that threaten human civilization, let alone "life as we know it". Although I am sure that some humans will be around in 2100, I am also pretty sure (given the total lack of meaningful action to reduce GHG emissions) that they will live in a different world. The Dutch, for example, will be forced to abandon two-thirds of their country. Americans will lose half of most coastal cities. San Franciscans will live in the hills, yes, but will they survive the hurricanes and ice storms? People in the developing world will face violence, famine and misery.

Bottom Line: A few years ago, I wrote that my dad's lifetime (roughly 1930-2030) was probably the best century we will ever live. Now I wonder if we're more likely to regret than enjoy the next few decades.*
* I was thinking of adding some advice about pricing water or carbon, etc., but I've said this often enough, without seeing much change. There's nothing new to add. Sorry.

23 comments:

Hi David, speaking about local warming, did you read anything about how soon the negative impacts of this ice melt will start affecting people significantly in their local communities? for example, when will US cities really start being negatively impacted by climate change: 2050-2060, 2060-2070...? how bad will the storms be for the cities in the next 10-20 years?-bad enough for them to significantly affect peoples lives?

"People in the developing world will face violence, famine and misery."

So same same, but I would argue that rich countries have a greater risk of famine given that we have organized our food economies for imports and paved or ruined our best arable land. People in the developing world are also often more resourceful in survival skills whereas we in urban and rich countries are very detached from skills that feed, clothe, and shelter us.

Weitzman is right when he says that it makes sense to shape policy in light of "fat tail" events, since their cost is immense. It is true that some scientists who are ardently concerned about climate change (e.g. Michael Mann) have concerns over Hansen's science in this paper, but applying Weitzman's logic, even if the probability that he is right is small, his views should still be taken into account in formulating policy.

@JP -- at US$50/ton CO2e, that would work out to about $0.44/gallon (EIA). The tax (what I call a Pigouvian fee) covers mitigation, but the revenue could be used for adaptation, lowering income taxes, etc.

I have read a portion of Weitzman paper. He is more educated on climate change than I will ever be. What is of most concern to me is that in order to address the CC issue we need to involve politicians/leaders. And in many nations, if not most, politicians usually address issues that can be implemented and effective within the political election cycle.

In short, if we can improve the quality of our politician's visionary capabilities we might be able to improve our collective vision for the future, of which CC is a critical part.

How do we improve the quality and visionary capabilities of our politicians/leaders?

I don't have the experience to address this question. Perhaps the most important thing I can do is vote. And looking at today's choices we have for electing the most powerful position in the political world I'm in a quandary.

Do you have any answers? I can only come up with questions. Maybe I should get my "Fat Tail" in gear. I'm trying to contribute to the issues facing our planet by moving water, but that is only one part of the puzzle that needs to be addressed.

ps/I just finished reading Weitzman's article. My conclusion is that our grandkids may be fucked, and we and earlier generations fucked them.

Even more disturbing is that for our grandkids to be saved, we the elders, must save them. Our leaders must have vision. And we must trust them when they present their visions. My earlier email described the difficulties in how this vision might be turned into reality.

This is a problem that calls for accepting a certain view of the future, the results of which may happen in a not so distant 100 years. Are we politically capable of implementing this vision? Are our grandkids capable of accepting our vision?

The answer is in questions that has been asked by man over 1,000's of generations. Where is the truth? Can we find it? Can we recognize it if we find it?

Jeez, it's scary. Honestly, you know what jumps out? I almost wish you would signal loud and clear in the intro paragraph that you're a libertarian and a believer in markets. So much of the opposition focuses on how it's a "democrat" issue and I think that as more and more people who don't identify as dems qualify that no, this is real - the more it widens the net. That principle of similarity, I suppose.

I've yet to see any evidence that humans are likely to solve the collective action problem that is CC. We just don't care enough about the future as far as I can tell. It's one of the few areas where I feel that libertarians have nothing to offer and that government is marginally better than markets, albeit still wildly insufficient. Personally I'm blindly hoping that some discovery or technological improvement will save us.

At what point do more extreme events begin to trigger more extreme responses? The point was made that politicians can lack vision but that does not necessarily mean that decision-makers will stand idly by as the consequences of CC pile up. It seems logical that as the severity of impacts from CC increase, then the scale of responses will do the same. A recent example from California illustrates this logic in action:

Would water managers in California be filling a major reservoir near Yosemite with black balls if the state was not experiencing severe drought? Most likely not. However, extreme conditions brought about these extreme "solutions."

So, what does this mean for some of the more unpopular ideas like geoengineering or nuclear power? Are we closer than we realize to a tipping point where these extreme responses become just as rational as dumping millions of black balls into a pristine wilderness area?

Good point but wouldn't you expect the lag between impacts and actions to be proportional to the scale of impacts? Smaller and more incremental impacts trigger slower and more incremental actions. Nuisance flooding during king tides might get some communities to start thinking about stockpiling sandbags. Meanwhile, Hurricane Katrina triggers $14 billion worth of flood protection projects, all constructed within a decade.

I think we have all heard the expression about politicians never wanting 'to let a good disaster go to waste.' It is sad and unfortunate but major disasters with major impacts drive signifiant investments in protection programs. Perhaps this reactive strategy is harmful to our generation but if it is a reliable trend then shouldn't we expect future (re)actions to scale alongside future impacts?

The problem with that assumption (which is often right) is that positive feedback makes it likely that we will see sealevel rise by a LOT, i.e., a "phase transition" from ice (on land) to water (in the sea) that is caused by temps rising a few degrees. If it was from -5 to -2C, it wouldn't matter, but -2 to +1 is a problem.

Agreed, there are plenty of problems with the assumption that infra investment will scale with climate impacts IF sea level rise accelerates passed a certain point. For gradual sea level rise, the (unfortunate) destruction-construction trend should continue at least until the residual risk in coastal areas becomes too high. For rapid sea level rise, you face impacts that can significantly outpace mitigation efforts. Both scenarios are problematic but the former is definitely more manageable than the latter.

Have you found any research suggesting a maximum rate of acceleration for SLR, passed which point we would have to abandon mitigation efforts and commit to relocation? This would be important to have in know if more extreme SLR forecasts are to become the norm.

The video below (@RD) has a scientist saying 3-4m in 2-3 years. That's pretty mch goodbye to a bunch of cities, based on existing infra and additional storm surge reach. I doubt even the Dutch could defend that much that fast. Lots of other places are going to be WAY more screwed.